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Re: GCC's -ffast-math behavior

ä 2012/2/10 13:52, Miles Bader åé: 


If you switch to using SSE floating-point, e.g. using "-mfpmath=sse",
it will still call the library functions even when using -ffast-math
(because the SSE unit doesn't have special instructions like "fsin" or
"f2xm1").  I think SSE FP is typically faster than the 387 for many
CPUs anyway.

Well, that's right.
But in my experience, -mfpmath=sse will slow my code very much.
I think -mfpmath=sse option has some bugs on X86.


--
Best Regards,
xunxun

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